Question

The compounds \(\mathrm{X}\) and \(\mathrm{Y}\) are obtained by the reaction \(\mathrm{of} \mathrm{C} \mathrm{l}_{2}\) with cold and dilute solution of \(\mathrm{NaOH}\) and \(\mathrm{X}\) and \(\mathrm{Z}\) are formed with hot and concentrated solution of \(\mathrm{NaOH}\). The \(\mathrm{Y}\) and \(\mathrm{Z}\) respectively are (1) \(\mathrm{NaCl}, \mathrm{NaClO}_{3}\) (2) \(\mathrm{NaClO}, \mathrm{NaClO}_{3}\) (3) \(\mathrm{NaCl}, \mathrm{NaClO}\) (4) \(\mathrm{NaC} 1 \mathrm{O}, \mathrm{HCl}\)

Short answer

The correct options are (2) NaClO, NaClO_3.

Step-by-step solution

Identify the Reaction Conditions

First, identify the conditions of the reactions given in the problem: 'cold and dilute solution of NaOH' and 'hot and concentrated solution of NaOH'. These conditions will help determine the products formed in each case.

Cold and Dilute NaOH Reaction

When \(\text{Cl}_2\) reacts with a cold and dilute solution of \(\text{NaOH}\), the reaction produces sodium chloride (\(\text{NaCl}\)) and sodium hypochlorite (\(\text{NaClO}\)). The reaction can be written as: \[ \text{Cl}_2 + 2\text{NaOH}_{(cold, dilute)} \rightarrow \text{NaCl} + \text{NaClO} + \text{H}_2\text{O} \] Thus, \(\text{X}\) is \(\text{NaCl}\) and \(\text{Y}\) is \(\text{NaClO}\).

Hot and Concentrated NaOH Reaction

When \(\text{Cl}_2\) reacts with a hot and concentrated solution of \(\text{NaOH}\), the reaction produces sodium chloride (\(\text{NaCl}\)) and sodium chlorate (\(\text{NaClO}_3\)). The reaction can be written as: \[ 3\text{Cl}_2 + 6\text{NaOH}_{(hot, conc.)} \rightarrow 5\text{NaCl} + \text{NaClO}_3 + 3\text{H}_2\text{O} \] Thus, \(\text{X}\) is \(\text{NaCl}\) and \(\text{Z}\) is \(\text{NaClO}_3\).

Match the Products

From the information above, \(\text{Y}\) is \(\text{NaClO}\) and \(\text{Z}\) is \(\text{NaClO}_3\). Therefore, the correct answer pair for \(\text{Y}\) and \(\text{Z}\) is: (2) \(\text{NaClO}, \text{NaClO}_3\).

Key concepts

cold and dilute NaOH reaction

When chlorine gas (\text{Cl}_2) reacts with a cold and dilute solution of sodium hydroxide (\text{NaOH}), it generates two specific compounds. This reaction is particularly important because it produces sodium chloride (\text{NaCl}) and sodium hypochlorite (\text{NaClO}).
The chemical equation for this reaction is:
\[ \text{Cl}_2 + 2\text{NaOH}_{(cold, dilute)} \rightarrow \text{NaCl} + \text{NaClO} + \text{H}_2\text{O} \]
This means you can expect to obtain \text{NaCl} and \text{NaClO} in a cold and dilute \text{NaOH} solution. Sodium hypochlorite is commonly used as a disinfectant or bleach, highlighting the practical importance of this reaction. Understanding this reaction helps in comprehending how different reaction conditions can change chemical outcomes.

hot and concentrated NaOH reaction

When chlorine gas (\text{Cl}_2) reacts with a hot and concentrated solution of sodium hydroxide (\text{NaOH}), the products are slightly different than in cold and dilute conditions. The products here are sodium chloride (\text{NaCl}) and sodium chlorate (\text{NaClO}_3).
The reaction can be expressed as:
\[ 3\text{Cl}_2 + 6\text{NaOH}_{(hot, conc.)} \rightarrow 5\text{NaCl} + \text{NaClO}_3 + 3\text{H}_2\text{O} \]
This yields primarily more \text{NaCl} and introduces sodium chlorate, which is often used in herbicides and explosives. By adjusting the temperature and concentration of \text{NaOH}, you can favor the formation of different useful products in industrial applications.

sodium chloride production

Sodium chloride (\text{NaCl}), commonly known as table salt, is a product in both cold, dilute and hot, concentrated sodium hydroxide reactions with chlorine gas. Its creation in these reactions is represented by:

• Cold, Dilute Reaction: \[ \text{Cl}_2 + 2\text{NaOH}_{(cold, dilute)} \rightarrow \text{NaCl} + \text{NaClO} + \text{H}_2\text{O} \]
• Hot, Concentrated Reaction: \[ 3\text{Cl}_2 + 6\text{NaOH}_{(hot, conc.)} \rightarrow 5\text{NaCl} + \text{NaClO}_3 + 3\text{H}_2\text{O} \]

In both reactions, \text{NaCl} is produced, emphasizing its consistent formation. \text{NaCl} is essential in food, pharmaceuticals, and many industrial processes.

sodium hypochlorite production

Sodium hypochlorite (\text{NaClO}) forms specifically when chlorine gas reacts with cold and dilute sodium hydroxide. It does not form in the hot and concentrated scenario. The chemical equation is:
\[ \text{Cl}_2 + 2\text{NaOH}_{(cold, dilute)} \rightarrow \text{NaCl} + \text{NaClO} + \text{H}_2\text{O} \]
\text{NaClO} is commonly used as a bleaching agent and disinfectant. Its importance stems from its effectiveness in purification processes, such as water treatment and sanitation. This reaction thus plays a crucial role in environmental and health-related applications.

sodium chlorate production

Sodium chlorate (\text{NaClO}_3) forms when chlorine reacts with a hot and concentrated sodium hydroxide solution, specifically under these conditions:
\[ 3\text{Cl}_2 + 6\text{NaOH}_{(hot, conc.)} \rightarrow 5\text{NaCl} + \text{NaClO}_3 + 3\text{H}_2\text{O} \]
\text{NaClO}_3 is involved in many industrial processes. It is utilized in herbicides, explosives, and even paper bleaching. This product's formation is a great example of how temperature and concentration variations can alter the outcome of chemical reactions to produce different useful compounds.